I reckon the documentation is supposed to document the beta_hardwareInterfaces branch already? Or should we rather create a corresponding branch for the documentation?
I would suggest to put a section "Hardware Interfaces" under "For developers" where we can describe the hardware interfaces API and show how to implement a new hardware interface and emphasize the design guidelines again.
Additionally I would suggest a categorie "Hardware Interfaces" with sections for each hardware interface under "Open Hybrid" where we describe the usage of the specific hardware interfaces.
And I think a categorie "Philosophy" or "About" or something like that where we can put the basic philosophy / guidelines stuff which can currently be found under "About" on the website would be good. I'm not sure if we should put it under "Getting started" or create a new categorie...